Michael Heseltine

He caused trouble for Margaret Thatcher and he is likely to cause trouble for May too. If the House of Lords are to make an impact they need Tory rebels, and Heseltine, a former deputy prime minister who is now a peer, is likely to be one of them when it comes to Brexit.

He was sacked from five government advisory roles for rebelling on a crucial Brexit vote. He argued that the House of Commons should “exercise its authority over the defining issue of our time.”

PARTY: Conservative

POSITION: Former deputy prime minister, now in the House of Lords

MP SINCE: 1974

REMAINIAC OR BREXTREMIST? Remain

Return to the full list of 40 Brexit troublemakers to discover who to watch as legislation disentangling Britain from the European Union goes through the U.K. parliament. For an explanation of how this list was compiled, see here.